springboot学习:属性赋值

心已赠人 2023-06-11 04:28 152阅读 0赞

### 1、@Value注解 ###

> 1、基本数值  
> 2、可以SpEl:\#\{\}  
> 3、可以写$\{\};取出配置文件的值

### 2、@PropertySource和@PropertySources注解 ###

> 使用@PropertySource读取外部配置文件中的key/value保存到运行环境变量中;加载完外部的配置文件以后使用$\{\}获取值

*  MainConfigOfPropertyValues类

@PropertySource(value = {"classpath:/person.properties"})
    //@PropertySources(value = {@PropertySource("classpath:/person.properties")})
    @Configuration
    public class MainConfigOfPropertyValues {
    	@Bean
    	public Person person() {
    		return new Person();
    	}
    }

*  Person类

@Value("")
    	private String name;
    	
    	@Value("#{20-2}")
    	private Integer age;
    	
    	@Value("${person.nickName}")
    	private String nickName;
    
    	public String getName() { return name; }
    	public void setName(String name) { this.name = name; }
    	public Integer getAge() { return age; }
    	public void setAge(Integer age) { this.age = age; }
    	public Person(String name, Integer age) { super(); this.name = name; this.age = age; }
    	public Person() { super(); }
    	@Override
    	public String toString() {
    		return "Person [name=" + name + ", age=" + age + ", nickName=" + nickName + "]";
    	}
    	public String getNickName() {
    		return nickName;
    	}
    
    	public void setNickName(String nickName) {
    		this.nickName = nickName;
    	}

*  Test1类

AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(MainConfigOfPropertyValues.class);
    	@Test
    	public void test1() {		
    		System.out.println(context.getBean(Person.class));
    		context.close();
    	}

*  person.properties文件

person.nickName=\u5F20\u4E09

*  目录结构  
    ![在这里插入图片描述][20191029102838924.png]
 *  输出结果  
    ![在这里插入图片描述][20191029102857766.png]

[20191029102838924.png]: /images/20230531/d7f284ec648e4bd88e4d0bed5e40c106.png
[20191029102857766.png]: /images/20230531/834a7e6369bd4baf8e35401aad741990.png